A certificate of incorporation is best favored by a recorded delivery. This is because a certificate of incorporation is a legal document issued by the Companies House in the UK, or a similar regulatory body in other countries, to confirm the creation of a limited liability company. It is a crucial document that proves the existence of the company, and as such, it is important that it is delivered securely to the intended recipient. Recorded delivery provides a form of proof of delivery, which ensures that the certificate is delivered to the right person and at the right address.